1. Field
The present disclosure relates generally to apparatus and methods for optimizing power consumption in electronic components, such as in a wireless device. More particularly, the present disclosure relates to methods and apparatus for optimizing power consumption through improvement of circuit response time in electronic components that employ dynamic clock and voltage scaling (DCVS) techniques.
2. Background
Optimizing power consumption in electronic devices is increasingly important, especially for devices such as battery-powered mobile devices. For user convenience, it is desirable that the operational time of a battery be extended as much as possible. There are numerous ways to extend the operational time for mobile devices including reducing the electrical load (i.e. DC current consumption) on the battery.
A way of accomplishing electrical load reduction is to optimize the power consumption of circuitry within a mobile device, such as by active power management of the electronic components within the mobile device. Active power management refers to dynamic techniques used to regulate the amount of DC current consumption depending on the current operational state. One way of dynamically regulating the power consumption of circuitry such as a processor or Central Processing Unit (CPU) is through Dynamic Clock and Voltage Scaling (DCVS). DCVS controls power consumption in a CPU, such as an application processor, as a function of utilization of the CPU. This is accomplished by monitoring the CPU utilization, and then dynamically changing the CPU clock frequency and voltage scaling of the operational voltage based on the monitored CPU utilization. For example, when the CPU utilization is increased relative to the clock frequency, the clock frequency is then dynamically increased, or when CPU utilization is decreased relative to clock frequency, the clock frequency is dynamically decreased, affording power savings when the CPU utilization is lower. Similarly, the voltage scaling may be modified in response to monitored CPU utilization. By dynamically adjusting the clock frequency and voltage of the CPU based on utilization, power consumption can be better optimized.
In future mobile wireless device designs, in particular, DCVS functionality could be moved into a modem processor in mobile wireless devices as well. Currently, known DCVS functionalities optimize response time for power consumption on an application processor that can tolerate a larger delay. If DCVS functionality is incorporated with a processor executing more time sensitive tasks, such as a processor executing one or more real-time activities in a modem processor that have strict time constraints for completions, known DCVS functions may not have quick enough response or processing time to change the frequency and/or voltage of the CPU to adequately process data and thus meet the requirements of all clients of the modem. In certain scenarios, usage of DCVS may result in a lower DC current consumption state with a slower transient response. In such cases, conventional DCVS may result in a processing response time that does not satisfy the needs of all processor clients.